仅需几周时间，这些药物就可将被感染者每毫升血液的艾滋病毒数量由数百万个减少到50个以内。

In a matter of weeks, these drugs reduce the number of viruses per millilitre of infected blood from millions to less than 50.

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在这种情况下，只有在几次呼吸不足出现，导致血液中二氧化碳大量增加和氧气减少后，呼吸的力度才得到调整。

Only after several inadequate breaths under such conditions, resulting in the considerable elevation of carbon dioxide and reduction of oxygen in the blood, is breathing effort adjusted.

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第二，一旦完全进入睡眠状态，非快速眼动期间血液中的二氧化碳增加，氧气减少。

Second, once sleep is fully obtained, there is an increase of carbon dioxide and a decrease of oxygen in the blood that persists during NREM.

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